Diagnostic Trouble Code (Dtc) P0440 Evaporative Emission (Evap) Control System Malfunction - Isuzu 1999 RODEO Workshop Manual

DIAGNOSTIC TROUBLE CODE (DTC) P0440 EVAPORATIVE EMISSION (EVAP)
Circuit Description
The evaporative system
components:
f Fuel tank
f EVAP vent solenoid
f Fuel tank pressure sensor
f Fuel pipes and hoses
f Fuel vapor lines
f Fuel cap
f EVAP canister
f Purge lines
f EVAP canister purge valve
f EVAP service port
The evaporative emission system is checked by applying
vacuum to the EVAP system and monitoring for a vacuum
decay. The PCM monitors the vacuum level through the
fuel tank pressure sensor signal.
At an appropriate time, the EVAP canister purge valve
and the EVAP vent solenoid are turned ON, allowing the
engine to draw a small vacuum on the entire evaporative
emission system. After the desired vacuum level has
been achieved, the EVAP canister purge valve is turned
OFF, sealing the system. If a sufficient vacuum level
cannot be achieved, a large leak is indicated. This can be
caused by the following conditions:
f Missing or faulty fuel cap
f Disconnected or faulty fuel tank pressure sensor
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
CONTROL SYSTEM MALFUNCTION
includes the following
f Disconnected, damaged, pinched, or blocked fuel tank
vapor line
f Disconnected or faulty EVAP canister purge valve
f Disconnected or faulty EVAP vent solenoid
f Open ignition feed circuit to the EVAP vent or purge
solenoid
f Damaged EVAP canister
f Leaking fuel sender assembly O–ring
f Leaking fuel tank or fuel filler neck
Any of the above conditions can set a Diagnostic Trouble
Code P0440. DTC P0440 is a type A code.
Conditions for Setting the DTC
f Diagnostic Trouble Codes P0106, P0107, P0108,
P0112, P0113, P0117, P0118, P0121, P0122, P0123,
P0125, P0131, P0132, P0133, P0134 and P1133 not
set.
f The BARO is greater than 72.3 kPa.
f IAT and ECT are between 3.5°C (38.5°F) and 90.5°F
at engine start up.
f The difference between IAT and ECT at start up is less
than 6.75°C (12.2°F).
f The Vehicle Speed is less than 98 km/h (60 mph).
f The Fuel Tank Level Sensor reads between 10% and
90%.
f Fuel Level counts vary by less than 15 counts in a
0.125 second time frame.
f Maximum Engine Run time is at least 540 seconds.
6E1–251
D06RX056